REPORT ON THE NEMERTEA. 



33 



" Postscript. — Since the above was written, my attention has been directed by 

 Dr. von Willemoes Suhm to Lesson's original figure of Pterosoma in the ' Zoology of the 

 Voyage of the Coquille ' (which work we have been able to consult, with a splendid series 

 of similar publications, in the Hawaian Government Library at Honolulu), and to the 

 many points of resemblance between Pterosoma and Pelagonemertes. 



Fio. 2.— Pelagonemertes rollestoni, Moseley, enlarged, viewed from the dorsal surface ; the proboscis is partly extruded. 

 P, proboscis ; PrS, sac of proboscis ; IP, invaginated portion of proboscis within the proboscis-sac ; G, superior nerve- 

 ganglion ; NC, nerve-cords ; V, vascular trunk (the upper V points to an enlargement of the vessel lying just 

 posteriorly to the superior nerve-ganglion) ; I, intestine ; D, diverticula of intestine ; 0,0, ovaries ; CM, circular 

 muscles ; LM, longitudinal muscles. 



" Pterosoma plana is described by M. Lesson, ' Voyage de la Coquille, Zoologie,' 

 Paris, 1830, p. 254, and figured, pi. iii. figs. 3 and 3 Us. Pterosoma was obtained in 

 great abundance by Lesson between the Moluccas and New Guinea, August 31, 1828. 



"The animals measured 3 inches and some lines in length, 18 lines in breadth, and 

 3 to 4 lines in thickness. In general form and gelatinous structure Pterosoma resembles 



(ZOOL. CHALL. EXP. — PAET LIV. — 1886.) 



Hhh 5 



